Japanese Yumi with the range of over 400 meters?

[Sagitarius Boemorum]

That is exactly what I m saing Bede. It stores lots of energy, but the limb recovery speed is rather low. Good for warbow, poor for flight bow.

I wonder how long will be a drawlenght of yumi with a weight of 100# or more as the wrist position so far and so high is very weak. With these weight the frame is limiting factor as well as shoulder compression.

I imagine 32?? would be average.....rather than 35??.


Jaro

[MJuingong]

Bede:

Did anybody try using those arrows and bow on a hardened target, e.g. hardened leather, any form of metal replica armor?

[Bede]

The arrows had standard Japanese target points, thin shells of brass, and were unsuitable for shooting at hard targets.

I have some Japanese armour-piercing arrow heads that I was thinking of mounting on arrows and testing. However, my skill at making bamboo arrows hasn't reach the level of making proper bamboo war arrows yet.

I think the idea that Japanese war arrows may have been around 32 inches is fair. The Japanese accounts though speak of large arrows. For instance in the story of Yoshitsune fighting at Sumiyoshi and Daimotsu, ther is this description:

To his three-man bow he affixed a humming bulb arrow thirteen hands and three finger-breadths long.

Admittedly, this arrow was supposed to have decapitated Teshima with its forked head! I assume it was meant to be a very large arrow to the contemporary readers. However, in defense of the descriptions in the book, I can say that they describe in detail the archery action including descriptions of bows, arrows and where in the quiver the arrows sat.

[Sinsigel]

[quote="Bede"]Shooting once with a Japanese archer at a layered cardboard target, the other archers (Western) and I (using a Korean bow in the Turkish style) noticed how much farther the Japanese target arrows penetrated the target. It averaged 20 inches farther than ours.[/quote]


That is an interesting example showing how well the arrow would perform when shot from appropriate bow. Did the other archers shot Japanese arrow with their bows at that "experiment"?

[Bede]

The nocks of the Japanese arrows were too narrow for the strings of the Western bows. My experience of drawing long arrows partially on shorter draw bows is uniformly bad. Their spine is affected and they are usually too heavy for the draw length.

[Sime]

I must admit that I do not fully understand famous energy storing thing. Shouldn't the bow for maximum efficiency have minimal limb mass + maximum draw length? If so, why are yumis made so long? I guess draw of the same length with also the same draw weight could be achieved with a shorter bow

[Bede]

In a world where bows were designed to one standard with particular goals in mind, you would be right. However, many cultures developed their bow designs over centuries by making small changes to existing designs. There was no pressure for major change until your neighbours started using bows that out ranged you or were more effective against your armour.

In the development of archery equipment, history and environment are more important than design. The Japanese developed a bow that was appropriate for their climate and for their style of hunting and warfare. Sometimes bows ended they way they are by accident. This doesn't mean that people didn't try to improve their equipment, but it was probably on a local level rather than on a national level.

[Tuukka Kumpulainen]

Using straight selfbows (Simon Stanley) to prove what was possible with Japanese bows in terms of cast is faulty. Japanese bows are made of hardened bamboo, laminated and severely reflexed, closer to hornbows than selfbows in their capacity to store energy and produce arrow velocities.

Some years ago a yumi shooter posted here the chrono results he obtained with recreational draw weights and heavy target arrows. A 44# bamboo yumi put 185fps into a 540 grain arrow, way over any self bow shooting over 12 grains per pound, while lighter (380gr.) arrows reached 206fps - a 270-yarder with low-cropped fletching and appropriate FOC.

No one is claiming the Japanese flight records were made with standard warbows. Just like 18th century Brits, I am sure the Japanese, too, made flight bows subtly different from ordinary bows: lower in mass, lesser in safety margins, with just a tad too light strings... and much faster.

What would a 90# Yumi, made with the goal of utmost cast, do with a flight arrow?

The traditional "full distance" in Japanese archery is 436 meters, shot using a flight arrow made from a one-year old bamboo shoot. The present Yumi flight record is 450 meters, and shot by Yamaha Gumbe (Stein 1988: 7.)

[Rapsod]

I think that you all forget dinamic forces. Dinamic forces are more inportant than static f/d curve.